Method of fabricating a semiconductor multi-package module having inverted land grid array (LGA) package stacked over ball grid array (BGA) package

Abstract

A method is provided for making a semiconductor multi-package module, by providing a lower molded ball grid array package including a lower substrate and a die, affixing an upper molded package including an upper substrate in inverted orientation onto the upper surface of the lower package, and forming z-interconnects between the upper and lower substrates.

What is claimed is: 
     
       1. A method for making a multipackage module, comprising:
 providing a BGA first package comprising a first package substrate, said BGA first package being a molded package, the molding having a generally planar upper surface; 
 providing a second package comprising a second package substrate; 
 inverting the second package and stacking the inverted second package over the first package, wherein stacking the inverted second package over the first package comprises applying an adhesive onto the molding upper surface and placing the inverted second package onto the adhesive; and 
 electrically interconnecting the first and second package by wire bonds connecting the first and second substrates. 
 
     
     
       2. The method of  claim 1  wherein the adhesive is a curable adhesive, and further comprising curing the adhesive. 
     
     
       3. The method of  claim 1  wherein providing the BGA first package comprises providing an unsingulated strip of BGA packages. 
     
     
       4. The method of  claim 1  where providing the BGA first package comprises testing BGA packages for a performance and reliability requirement and identifying the said first package as meeting the requirement. 
     
     
       5. The method of  claim 1  where providing the second package comprises testing packages for a performance and reliability requirement and identifying the said second package as meeting the requirement. 
     
     
       6. The method of  claim 1 , further comprising attaching second-level interconnect balls onto the BGA first package substrate. 
     
     
       7. The method of  claim 1 , further comprising encapsulating the stacked packages in a multipackage module molding. 
     
     
       8. The method of  claim 1 , further comprising singulating the modules. 
     
     
       9. The method of  claim 1  wherein providing the second package comprises providing a land grid array package. 
     
     
       10. The method of  claim 1  wherein providing the second package comprises providing a land grid array package, the land grid array package being at least partially molded. 
     
     
       11. The method of  claim 10 , the land grid array package being fully molded. 
     
     
       12. The method of  claim 10 , the wire bonds of the land grid array package being molded, and at least a portion of an upward facing surface of an upper die being exposed. 
     
     
       13. The method of  claim 1  wherein the BGA first package is provided with an electromagnetic shield affixed over the die. 
     
     
       14. The method of  claim 13 , the shield having a generally planar upper surface, wherein stacking the inverted second package over the first package comprises applying an adhesive onto the shield upper surface and placing the inverted second package onto the adhesive. 
     
     
       15. The method of  claim 14  wherein the adhesive is a curable adhesive, and further comprising curing the adhesive. 
     
     
       16. The method of  claim 1 , further comprising providing a heat spreader. 
     
     
       17. The method of  claim 16 , wherein providing a heat spreader comprises carrying out a drop-in mold operation, the heat spreader being placed into a mold prior to forming a module molding. 
     
     
       18. The method of  claim 16 , wherein providing a heat spreader comprises affixing a generally planar portion of a heat spreader onto a generally planar upward facing surface of the inverted second package.